Description
applicableWeight sums applicable items; observedWeight additionally requires observed.
Assessment coverage can refer to scored items, applicable items, observation counts or total weights. A support share depends on those choices and is separate from a final score, a validated scale or an inference about a learner.
applicableWeight sums applicable items; observedWeight additionally requires observed.
When to use this tool
Use Item Observation Support Share when checking an explicit assessment or observation-support denominator.
How to use the tool and how it works
- Enter itemIds, observed, applicable, weights. Keep parallel arrays aligned. Use the units and conventions below.
- Run the tool. Correct any format, range, or cross-field input error before interpreting the output.
- Read applicableWeight, observedWeight, share, defined. Inspect defined before interpreting the associated values.
Require equally long itemIds, observed, applicable and weights, unique item IDs and nonnegative weights. applicableWeight sums applicable items; observedWeight additionally requires observed. share is their ratio when applicableWeight > 0, otherwise zero with defined = false.1
| Input field | Meaning and units | Accepted input |
|---|---|---|
| itemIds | Item Ids | Required. Array of text; maximum UTF-16 length 8192; maximum items 256. |
| observed | Position-aligned flags specifying which records are observed. | Required. Array of boolean; maximum items 256. |
| applicable | Applicable | Required. Array of boolean; maximum items 256. |
| weights | Position-aligned nonnegative weights under the specified model convention. | Required. Array of finite number; minimum 0; maximum items 256. |
| Output field | Interpretation | Returned shape |
|---|---|---|
| applicableWeight | Applicable Weight | Required. Finite number. |
| observedWeight | Observed Weight | Required. Finite number. |
| share | Dimensionless selected contribution divided by the stated total; not percent. | Required. Finite number. |
| defined | Whether the stated denominator has positive support; read this before interpreting a zero placeholder. | Required. Boolean. |
{
"input": {
"itemIds": [
"a",
"b"
],
"observed": [
true,
false
],
"applicable": [
true,
true
],
"weights": [
2,
3
]
},
"output": {
"applicableWeight": 5,
"observedWeight": 2,
"share": 0.4,
"defined": true
}
}Limitations and assumptions
- This is weighted support inside a supplied applicability mask, not a complete test score or validation of missingness assumptions.
- Inputs must satisfy both the field types and the cross-field conditions above. Invalid input causes an error; a successful false flag or documented placeholder is a different result.
- Numeric calculations use binary floating point unless exact decimal-integer arithmetic is explicitly stated. No hidden measurement tolerance or decimal rounding is added; nonfinite or out-of-contract results are rejected. Numeric signed-zero results are exported as zero.
Alternative or Complementary methods
Review the assessment design, missing-item policy and observation method before interpreting coverage as valid achievement evidence.
References
Similar or alternative tools
- Question Bank Exposure One Item Term
exposureFraction = seen/administrations.
- Test Item Unscored Weight Budget
Separate total assessment weight into scored and unscored portions.